A Los Angeles County Sheriff’s employee is in critical stable condition Thursday after he fell from the roof of the department’s four-story headquarter’s building on Wednesday, Monterey Park Police officials said.

The unidentified 49-year-old maintenance worker, who was assigned to the department’s headquarters, fell about 45-feet around 1:13 p.m. at 4700 Ramona Road, officials said.

Sgt. Frank Duke said the man sustained major internal injuries from his neck down.

“We’re hoping to speak with him in the next two days and it will answer a lot of questions as to what happened,” Duke said.

Police do not suspect criminal activity.

The Division of Occupational Safety and Health was at headquarters Thursday, investigating why the employee was on the roof, Duke said.

“I don’t know if he was supposed to be on the roof,” he said. “It’s not a police matter.”

The man was transported to Los Angeles County USC Medical Center.

Duke said the man has been employed with the sheriff’s department since 2001.